Millstone-driver



nted May 15,1883.

J. DEMPSTEP. MILLSTONE DRIVER.

Pate

I (No Model.) 7

Ell!! I ATTORNEYS.

UNITED, STATES PATENT OFFICE;

JOHN DEMPSTER, OF KNOXVILLE, TENNESSEE.

MlhLSTONE-DRIVER.

SPECIFICATION forming part of Letters Patent No. 277,688, dated May 15,1.883.

Application filed December 27, 1882.

To all whom it may concern:

Be it known that I, .IoHN DEMPSTER, a citizen of the United States,residing at Knoxville, in the county of Knox and State of Tennessee,have invented a new and Improved Millstone-Driver, of which thefollowing is a specification.

My invention relates to that class of millstones in which the shaftorspindle stands vertically and suppotts the stone by means of a ryndresting upon the upper end of the spindle or cock-head; and my object isto provide means whereby the runner-stone may be balanced on thecock-head and be operated in running balance, and means wherebytherunner-stone may also be rigidly secured to the spindle and truedthereon.

To this end my invention consists in the construction and combination ofparts hereinafter fully described and claimed, reference being had tothe accompanying drawings, in which- Figure l is a central verticalsection, showing my invention attached toan upper runner millstone. Fig.2 is an inverted plan of the same.

A represents the runner-stone, made up in this instance by the commonprocess of using burr-stone blocks and cement, which I build around andfirmly join to a cylindrical casting, B, forming the eye of the stone ofpeculiar construction. The exterior of this cylinder may be shaped inany desired form to hold fast in the cement between the stone blocks,and its height will correspond to the height of the stone, less theamount of stone which is assigned for wear and to be cut away in dress.-ing the face of the stone during its lifetime. I provide the interior ofcylinder B with two sets of grooves, D E, each set consisting of threeor more grooves.

F represents ears projecting from the cylin der B into the eye overgrooves D, and provided with screw-threaded holes.

frepresents adjustingscrews passing down through the ears F andsupporting the stone by their points resting on the horns of thebalance-rynd d. The horns fit closely, yet admit of vertical adjustmentin grooves D. This rynd has the usual cock-eye to fit upon the cock-headg of the spindle G.

cisanother rynd, which I call the rigid (No model.)

driver, whose horns fit closely but have vertical play in grooves E.Rynd c is keyed firmly to the spindle below the cock-head, and serves asthe driver, communicating motion from the spindle to the stone throughthe walls of grooves E or D. The stone is hung in balance by means ofrynd d, resting on the cock-head and supporting the stone upon the adjListing-screws f. hen thus hung the stone is revolved by the driver 6,placed in the grooves E, which extend the whole height of the inner faceof the cylinder B.

To-hang the stone rigidly upon the spindle to run therewith, thebalance-ryud d is removed and the grooves D are placed upon the horns ofthe fixed rynd or driver 0, and adjusted to bring the face of the stonetrue with the face of the bed-stone by means of the aforesaidadjusting-screws f. The horns of this rynd fit grooves D more closelythan they fit grooves E, in order that the stone may run rigidly withthe spindle in the latter case, and with some freedom with respectthereto in the former case. This is accomplished by the grooves E beingslightly wider than grooves D and the horns of the two rynds being ofequal width. When hung upon the spindle by means of the balance-rynd cland driven by the rigid rynd 6 my millstone has all the adaptability offine meal or fiour grinding stones. When the balance-rynd is removed.and the stone is rigidly hung to the spindle by means of the rigiddriver, as described, it is adapted to grannlate wheat by being adjustedparallel to the bed-stone, and so revolved at any fixed distance desiredtherefrom. By this means of hanging burr-stones I am able to granulatewheat in a superior manner and to. produce a large percentage ofmiddlings relative to the What I claim as my invention is-- 1. Thecombination, with a cast-iron cylinderforming the eye of a millstone,provided internally with two sets of vertical grooves and screw-earsover one set of said grooves, of two rynds and a spindle, all asdescribed, for the purpose specified.

2. The runner-stone, the cylinder 13, provided with thetwo sets ofinternal grooves, D and E, and a set of screw-ears, I, and the screwsf,in combination with aspindle, Gr,havin g a cock-head, g, abalance-rynd, 0?, provided with a cock-eye, and 2t (lriving-rynd, e,

rigidly keyed to said spindle, as shown and described.

3. The combination, with the runner-stone,

5 the cylinder B, forming the eye thereof, and

having two sets of grooves, D and E, and the screw-ears F, the screws f,and the spindle G,

of two rynds, both fitted to occupy the grooves D, one rynd beingrigidly keyed to the spindle 10 at all times and the other adapted to bebalother time be rigidly secured to the spindle,

for the purposes specified.

JOHN DEMPSTEB.

Witnesses:

JAS. A. SooTT, CHAS. HOPKINS.

